The present invention relates generally to an integrated circuit (IC) design, and more particularly to light emitting technologies that can be produced in the same substrate along with a control circuit device.
Light emitting technology has been one of the fastest growing industries in recent years. The improvement in the technology has shrunk the size of many products such as computer displays by providing new generations of products such as the liquid crystal displays (LCD).
One conventional method for fabricating a light emitting device today is to implant a number of ultra-fine particles, which are also known as nanocrystals, into a thick dielectric layer above the silicon surface. These nanocrystals can be made of materials such as silicon (Si), germanium (Ge), or a combination of the two materials (SiGe). The dielectric layer is made of silicon-oxide (SiO2), and it is a proven combination of materials that provides good control over the fabrication process.
However, this conventional method suffers from various critically important pitfalls. For example, it provides a poor gate dielectric layer interface, which reduces the ability to optimally form nanocrystals into the dielectric layer above the silicon surface. The CMOS device performance may also be poor due to poor hole mobility. The thick SiO2 dielectric layer also means a higher material cost during fabrication. It is also difficult to combine the light emitting devices and control circuit devices on the same substrate with this conventional method. This is a major issue since the light emitting devices need to be assembled with many VLSI control circuit devices.
It is therefore desirable to design methods for a fabricating light emitting device that can be easily integrated with a control circuit without driving up fabrication cost.